brake bleeding troubleshooting
Thread Starter
Drifting
Joined: Sep 2002
Posts: 1,614
Likes: 7
From: South Florida
brake bleeding troubleshooting
I have the stock brake system, no power 69. Brake system was completely rebuilt. I'm running DOT5. The system worked 8 months ago before paint. When the car went to paint, the MC was removed.
I bench bled the MC and reinstalled. I am vacuum bleeding the system. I can almost get the bubbles out of the rear calipers, though I'm still getting what looks like foam in the LR outside valve.
The front calipers seem like they are spitting out 80% air and some old brake fluid.
New brake fluid came through the rears, only old fluid is coming out the front bleeders.
I removed the lines from the MC and bench bled it on the car. I got a little bit of air in the front and rear resivoirs but none now. Reinstalled the MC lines and tightened the front line fittings.
Still getting bubbles and air noise when bleeding the front callipers.
I feel like I'm drawing air into the system, but can't find any leaks. The brakes worked better than they ever had 8 months ago for over a years worth of time.
Suggestions?
I bench bled the MC and reinstalled. I am vacuum bleeding the system. I can almost get the bubbles out of the rear calipers, though I'm still getting what looks like foam in the LR outside valve.
The front calipers seem like they are spitting out 80% air and some old brake fluid.
New brake fluid came through the rears, only old fluid is coming out the front bleeders.
I removed the lines from the MC and bench bled it on the car. I got a little bit of air in the front and rear resivoirs but none now. Reinstalled the MC lines and tightened the front line fittings.
Still getting bubbles and air noise when bleeding the front callipers.
I feel like I'm drawing air into the system, but can't find any leaks. The brakes worked better than they ever had 8 months ago for over a years worth of time.
Suggestions?
Thread Starter
Drifting
Joined: Sep 2002
Posts: 1,614
Likes: 7
From: South Florida
Update:
Before I read your responses, I switched to pumping the brakes. I am building pressure in the peddle. The fluid coming out is new in the rears, as it is purple. There are no bubbles this way. I switched back to vacuum...lots of bubbles.
I was wondering about sucking air around the bleeders. When I apply vacuum on a closed blessed, I see a little bit of fluid moving in the tube...like residual fluid.
Yes, the original style seals.
Before I read your responses, I switched to pumping the brakes. I am building pressure in the peddle. The fluid coming out is new in the rears, as it is purple. There are no bubbles this way. I switched back to vacuum...lots of bubbles.
I was wondering about sucking air around the bleeders. When I apply vacuum on a closed blessed, I see a little bit of fluid moving in the tube...like residual fluid.
Yes, the original style seals.
Thread Starter
Drifting
Joined: Sep 2002
Posts: 1,614
Likes: 7
From: South Florida
Update: problem fixed.
Vacuum bleeder was drawing air around the threads of the blessed valves. Brakes are bled with good peddle. I used teflon tape on the bleeder valves.
Went around the car and manually bled afterwards to double check.
Thanks for the help guys. The car is taking a trip in a week and I was running out of time.
Vacuum bleeder was drawing air around the threads of the blessed valves. Brakes are bled with good peddle. I used teflon tape on the bleeder valves.
Went around the car and manually bled afterwards to double check.
Thanks for the help guys. The car is taking a trip in a week and I was running out of time.
Melting Slicks
Joined: Aug 2008
Posts: 2,200
Likes: 3
From: Lehigh county Pennsylvania
Since there seems to be an endless amount of brake bleeding questions, this tip should be included in the consolidated tips sticky. More DIYer's need to be made aware of this condition.
